I’m an avid tea drinker. I love tea, especially green tea, and all of the benefits it can offer. For example, green tea improves health and promotes weight loss. And mint tea can help with stomach aches. One thing I’m wondering is if tea can cause kidney stones. My friend posed this question to me a few weeks ago, and ever since then, that question has been swirling around my head— especially if I’m drinking a cup of tea.

According to EverydayHealth.com, an article they published stated that drinking iced tea may cause kidney stones. The article notes that because tea consists of oxalates,  kidney stones have an increased chance of forming in the kidneys. An oxalate is a common chemical that causes kidney stones to form. The article also points out that iced tea has a greater chance of creating kidney stones than hot tea. And while tea may contain oxalate, does correlation equal causation?

For example, while oxalates may be correlated with creating kidney stones, this does not necessarily mean it is the cause. Many other factors can attribute to causing kidney stones. These factors, confounding variables, could be the solution to this question of whether tea causes kidney stones or not. Some possible third variables may include genetics, gender, exercise, diet and age. And of course, chance could always be the answer to the hypothesis.

According to DiscoverTea.com, an article they published stated that different types of tea contains different levels of oxalates. The article further notes that a Japanese study concluded that green tea can even help prevent the formation of kidney stones. Additionally, the article points out that all of the studies used tea bags, and not loose tea.

I would probably conduct my own experiment and compare my results and data to determine if iced tea can cause the formation of kidney stones. I would perform a meta-analysis and gather two groups of people. One group would drink iced tea, and the other group would not. I would then compare both groups and determine how many people formed kidney stones. I’m interested to find out what the results would be, but I assume the group who drank the iced tea would have an increased number of kidney stones formed versus the non-tea drinking group.

While tea may have a lot of benefits, certain teas, especially of the iced variant, may cause kidney stones. But don’t fret, because some teas, like green tea, can have the opposite effect and actually prevent kidney stones. Be aware of what kinds of tea you’re drinking, but don’t be too concerned. Kidney stones are not a major health hazard, and they pass naturally through the body.

Unless you’re Joey from Friends, and it’s an unbearable experience all around.